Atypical Hemolytic-Uremic Syndrome with Positive Direct Coombs Test: Case Study

Background. Atypical hemolytic-uremic syndrome (aHUS) is an orphan chronic systemic disease resulting from uncontrolled activation of alternative complement pathway and development of complement mediated-thrombotic microangiopathy (TMA). Its diagnosis can be challenging even in cases with classic signs.

Case description. This study describes clinical case of aHUS in 5 years old child. Disease diagnosis was associated with significant difficulties due to Coombs-positive hemolytic anemia. aHUS diagnosis was established based on recurrent course of TMA with a reduced level of complement C3 component and signs of multiple organ damage. Eculizumab administration led to rapid remission.

Conclusion. aHUS course is progressive and has unfavorable prognosis with no pathogenetic therapy. Its timely diagnosis, mainly based on exclusion of other etiological factors of TMA, allows us to prescribe complement-blocking therapy. Such treatment prevents the development of multiple organ damage and promote stable remission along with supportive therapy.

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